/sci/ - Science & Math

File: 8 KB, 600x650, bingocard.png [View same] [iqdb] [saucenao] [google]

Anonymous Tue Jul 5 11:06:53 2011 No.3337005 [Reply] [Original]

Can we have a puzzle threads? Do you guys do puzzle threads? I'll start with an easy one.

Bingo is a game almost everyone knows. Tokens are placed on a 5x5 board depending on whether or not a number on the one of the squares is called. One free token is placed in the middle. When you get five tokens in a row horizontally, vertically, or along the two diagonals, you get a bingo and win.

What is the maximum number of tokens you can place on a bingo card, counting the free token, without getting a bingo?

>>	Anonymous Tue Jul 5 11:11:53 2011 No.3337021 bump. Anyone got any other puzzles?

>>	Anonymous Tue Jul 5 11:13:53 2011 No.3337030 is it 20?

>>	Anonymous Tue Jul 5 11:17:53 2011 No.3337045 >>3337030 its 16, actually

>>	EK !EKFQOBUFnQ Tue Jul 5 11:18:37 2011 No.3337049 File: 31 KB, 627x679, bingo_20.jpg [View same] [iqdb] [saucenao] [google] i get 20.

>>	Anonymous Tue Jul 5 11:20:53 2011 No.3337050 >>3337049 You got it! Nice job, man.

>>	Anonymous Tue Jul 5 11:20:53 2011 No.3337052 >>3337045 You can fit 20 on trivially

>>	Anonymous Tue Jul 5 11:21:53 2011 No.3337057 Also trivial to show the upper bound is 20

>>	Anonymous Tue Jul 5 11:21:53 2011 No.3337058 puzzle is easy as shit. one empty square in each row. different column for empty square each time. make sure there's an empty on each diagonal.

>>	Anonymous Tue Jul 5 11:22:53 2011 No.3337064 Next puzzle?

>>	EK !EKFQOBUFnQ Tue Jul 5 11:23:37 2011 No.3337067 >>3337050 thank >030, they were first.

>>	EK !EKFQOBUFnQ Tue Jul 5 11:26:37 2011 No.3337075 >>3337064 A 2 digit number: 'AB' is multiplied by 7 and then divided by 4. this number is now 'BA' (digits have been reversed) what is AB?

>>	Anonymous Tue Jul 5 11:28:53 2011 No.3337082 >>3337075 00

>>	EK !EKFQOBUFnQ Tue Jul 5 11:29:37 2011 No.3337087 >>3337082 huh... lol that works, didnt think of that. lol, well played =p can you name another one?

>>	Anonymous Tue Jul 5 11:31:53 2011 No.3337100 >>3337075 21 42 63 84 basic algebra gtfo

>>	Anonymous Tue Jul 5 11:31:53 2011 No.3337101 >>3337100 Mean.

>>	EK !EKFQOBUFnQ Tue Jul 5 11:34:37 2011 No.3337116 >>3337100 yeh those work. fine, i'll make a better puzzle...

>>	Anonymous Tue Jul 5 11:35:53 2011 No.3337121 >>3337116 it's funny cos you were probably unable to come up with those answers prove me wrong bro, come at me

>>	pascal !n5Z3VuZapw Tue Jul 5 11:35:53 2011 No.3337122 >>3337049 There is a diagonal bingo there

>>	EK !EKFQOBUFnQ Tue Jul 5 11:37:37 2011 No.3337126 >>3337122 is only 2 diagonals on a bingo grid, A5 and E1 arn't filled in so one diagonal is blocked twice. D4 is not filled in, which blocks the second diagonal

>>	Anonymous Tue Jul 5 11:37:53 2011 No.3337127 >>3337122 idiot

>>	Anonymous Tue Jul 5 11:37:53 2011 No.3337128 >>3337122 Point it out or hold your tongue!

Anonymous Tue Jul 5 11:37:53 2011 No.3337130
File: 16 KB, 800x400, hat puzzle.png [View same] [iqdb] [saucenao] [google]

OP here, back with another one I remember, but this and bingo are pretty much the only good puzzles I can think of.

4 men, A, B, C, and D, are lined up in a row. Between A and the other three is a wall that he can't see through. The black dots are eyes; they represent which way the men are looking. A and B can only see the wall. C can see B. D can see both B and C.

The men are told this; they are not allowed to move. They are not allowed to speak. They are not allowed to take off their hats. One of them must correctly state whether their hat is black or white within five minutes or they will all be killed.

One of the men correctly figure out whether their hat is black or white within five minutes. They are 100% certain. Which man is it? Why are they certain?

>>	EK !EKFQOBUFnQ Tue Jul 5 11:38:37 2011 No.3337132 using the digit '8' exactly 8 times, along with any mathematical symbols you like, make it total 1000.

>>	Anonymous Tue Jul 5 11:39:53 2011 No.3337137 >>3337130 I assume they are told beforehand that there are two white hats and two black hats?

>>	Anonymous Tue Jul 5 11:39:53 2011 No.3337139 >>3337130 They're not told anything about how many hats of each colour there are?

>>	Anonymous Tue Jul 5 11:40:53 2011 No.3337147 >>3337137 >>3337139 Oh yeah! Whoops, sorry about that. THe men are told that there are two hats and two black hats.

>>	Anonymous Tue Jul 5 11:40:53 2011 No.3337148 >>3337147 two WHITE hats and two black hats. Holy fuck.

>>	Anonymous Tue Jul 5 11:41:53 2011 No.3337152 >>3337130 C. easy as poop. i won't spoil it for others.

>>	Anonymous Tue Jul 5 11:42:53 2011 No.3337154 >>3337147 In that case "c" will be the first.

>>	Anonymous Tue Jul 5 11:45:53 2011 No.3337161 File: 9 KB, 800x800, circle.png [View same] [iqdb] [saucenao] [google] What is the maximum number of pieces that you can cut this circle into with only 6 straight cuts?

EK !EKFQOBUFnQ Tue Jul 5 11:46:37 2011 No.3337169 [DELETED]

>>3337130
>>3337147

if C does not hear D speak immediately, then b and C do not have the same colour hat. C can see b's hat, and must know he has a different colour to him, so he will say his hat is black.
unless D is very fucking slow, or retarded, or a jerk.

>>	Anonymous Tue Jul 5 11:47:53 2011 No.3337172 >>3337161 16?

>>	Anonymous Tue Jul 5 11:49:18 2011 No.3337178 >>3337169 EK = whole day on 4chan. lol

>>	Anonymous Tue Jul 5 11:50:53 2011 No.3337180 >>3337161 Ugh, there was some way to figure out how many intersections there can be between lines. 15?

>>	Anonymous Tue Jul 5 11:51:53 2011 No.3337191 File: 42 KB, 800x800, 1309880703256.png [View same] [iqdb] [saucenao] [google] >>3337161

>>	Anonymous Tue Jul 5 11:52:53 2011 No.3337193 File: 38 KB, 800x800, Untitled.png [View same] [iqdb] [saucenao] [google] I get 18

>>	Anonymous Tue Jul 5 11:53:53 2011 No.3337196 You guys don't have it yet, keep going!

>>	pascal !n5Z3VuZapw Tue Jul 5 11:53:53 2011 No.3337197 >>3337128 >>3337127 >>3337126 Sorry looked at thumbnail wrong

>>	Anonymous Tue Jul 5 11:55:53 2011 No.3337206 File: 24 KB, 859x609, 22.png [View same] [iqdb] [saucenao] [google] 22

>>	Anonymous Tue Jul 5 11:56:53 2011 No.3337210 (n^2+n+2)/2 n=6 gives 22 lines

>>	Anonymous Tue Jul 5 11:56:53 2011 No.3337213 >>3337197 That's fine. What've you been up to today?

>>	Anonymous Tue Jul 5 11:57:53 2011 No.3337217 File: 20 KB, 800x800, 6.png [View same] [iqdb] [saucenao] [google] i gots 19

>>	Anonymous Tue Jul 5 11:57:53 2011 No.3337218 >>3337180 20, I can prove it.

>>	Anonymous Tue Jul 5 11:58:53 2011 No.3337222 >>3337193 move the central vertical line left slightly congratulations, you have created a new piece you will never be a mathematician

>>	Anonymous Tue Jul 5 11:58:53 2011 No.3337227 >>3337222 And I am grateful for that.

>>	Andrew Stevens Tue Jul 5 12:00:53 2011 No.3337233 >>3337045 no, it's 20

>>	pascal !n5Z3VuZapw Tue Jul 5 12:00:53 2011 No.3337235 >>3337213 Work

>>	Anonymous Tue Jul 5 12:01:53 2011 No.3337236 >>3337227 $300K starting any job i want enjoy your beans

>>	Anonymous Tue Jul 5 12:01:53 2011 No.3337239 >>3337206 No, it's 20.

>>	Anonymous Tue Jul 5 12:02:53 2011 No.3337242 UBER CHALLENGE: how many pieces can you cut a circle into with 6 lines? AND explain how you worked it out and write a proof. if you genuinely did the question this shouldn't be hard. if you googled, your faggotry has been exposed.

>>	Anonymous Tue Jul 5 12:02:53 2011 No.3337244 >>3337210 ((n^2+n+2)/2)-2 n=6 gives 20 lines No, it's 20.

>>	Anonymous Tue Jul 5 12:03:53 2011 No.3337250 >>3337236 Ouch, the materialism. I get to travel abroad for 6 months a year. Enjoy your basement.

>>	Anonymous Tue Jul 5 12:05:53 2011 No.3337255 >>3337242 Late to the party... See >>3337161

>>	EK !EKFQOBUFnQ Tue Jul 5 12:07:37 2011 No.3337259 >>3337206 i got 22 as well, this works.

>>	Anonymous Tue Jul 5 12:07:53 2011 No.3337262 >>3337242 The answer is 20.

>>	PUZZLE 3 EK !EKFQOBUFnQ Tue Jul 5 12:09:37 2011 No.3337270 File: 28 KB, 609x646, knight_grid.jpg [View same] [iqdb] [saucenao] [google] still waiting on puzzle 2, see: >>3337132 PUZZLE 3 <<< you are a chess-knight start anywhere you like, but you must hit each square once and only once.

>>	Anonymous Tue Jul 5 12:09:53 2011 No.3337271 >>3337259 EK, you're always wrong.

>>	EK !EKFQOBUFnQ Tue Jul 5 12:11:37 2011 No.3337277 >>3337271 my picture looked messier, but 22 DOES work. his pic is proof, fucking count it!

>>	EK !EKFQOBUFnQ Tue Jul 5 12:12:37 2011 No.3337283 >>3337270 btw, squares are numbered, so you can post answers here in the form 1,13,6,2,8... etc. but all moves have to be legitimate chess knight moves on the grid.

Anonymous Tue Jul 5 12:13:53 2011 No.3337285

>>3337255
>>3337262

holy shit you guys are stupid. how the fuck do you not recognise the difference between my question and the previous one?

HUR DUR ITS TWENTEE COS I BEN ON TEH WIKEPED

how do you know this is the best solution? PROVE it, that's the real question.

>>	Anonymous Tue Jul 5 12:16:53 2011 No.3337299 >>3337270 5 12 3 10 16 7 1 9 11 2 8 15 13 17 14 Did it on my first try :P

>>	Anonymous Tue Jul 5 12:17:53 2011 No.3337302 >>3337270 29

>>	Anonymous Tue Jul 5 12:17:53 2011 No.3337305 File: 42 KB, 609x646, Too easy.jpg [View same] [iqdb] [saucenao] [google] >>3337270

>>	Anonymous Tue Jul 5 12:21:53 2011 No.3337322 >>3337285 (n+14) n=6 there are 20 intersects

>>	Anonymous Tue Jul 5 12:22:53 2011 No.3337327 >>3337130 C. He can see the white hat in front of him and he knows that if he also had a white hat, D would immediately say he had a black hat.

>>	Anonymous Tue Jul 5 12:23:53 2011 No.3337332 >>3337299 5 12 3 10 16 7 1 9 11 2 8 15 6 4 13 17 14 My bad left out 6 and 4...

>>	Anonymous Tue Jul 5 12:26:59 2011 No.3337344 File: 51 KB, 609x646, 1309882156194.png [View same] [iqdb] [saucenao] [google] >>3337270 landed on everyone cant be arsed posting order. dont care if you dont believe me

>>	EK !EKFQOBUFnQ Tue Jul 5 12:28:37 2011 No.3337354 File: 239 KB, 482x343, zh5.png [View same] [iqdb] [saucenao] [google] >>3337305 >>3337299 >>3337344 well done to everyone who solved it, i'll trust that >344 did it right (ive confirmed the other 2) :)

>>	Anonymous Tue Jul 5 12:28:53 2011 No.3337351 >>3337344 wat

>>	Anonymous Tue Jul 5 12:29:53 2011 No.3337358 >>3337132 I got it in 9 uses of "8"... <span class="math">(88*88/8)+8+8+8+8[/spoiler]

>>	Anonymous Tue Jul 5 12:30:53 2011 No.3337363 >>3337270 puzzle 3 V2, how many ways can you solve this

>>	EK !EKFQOBUFnQ Tue Jul 5 12:31:37 2011 No.3337365 >>3337358 8 digits only please. there are multiple solutions. GENIUS MODE: complete it using only addition. (is possible)

>>	Anonymous Tue Jul 5 12:31:53 2011 No.3337366 >>3337132 888+(8+8)8-8-8 (for seven times 8: (8+8)88-8-8-8) (for nine times 8: 8888/8+8+8+8+8)

>>	Anonymous Tue Jul 5 12:33:18 2011 No.3337373 > mfw EK doesn't know that addition is associative > and 8 + 8 + 8 + 8 + 8 + 8 + 8 + 8 isn't 1,000 > just gtfo out and educate yourself ffs

>>	EK !EKFQOBUFnQ Tue Jul 5 12:33:37 2011 No.3337369 File: 247 KB, 401x332, zh4.png [View same] [iqdb] [saucenao] [google] >>3337366 correct!

>>	EK !EKFQOBUFnQ Tue Jul 5 12:33:37 2011 No.3337375 File: 3 KB, 125x95, zh1.jpg [View same] [iqdb] [saucenao] [google] >>3337370 >>3337372 yes! well done!

>>	Anonymous Tue Jul 5 12:33:53 2011 No.3337370 >>3337365 888+88+8+8+8

>>	Anonymous Tue Jul 5 12:33:53 2011 No.3337372 >>3337365 888 + 88 + 8 + 8 + 8

>>	Anonymous Tue Jul 5 12:34:18 2011 No.3337376 >>3337354 >>3337369 EK my love, when can we meet?

>>	Anonymous Tue Jul 5 12:36:18 2011 No.3337384 >>3337132 > mfw yet another math problem turns out to allow concatenation as a mathematical operation

>>	Anonymous Tue Jul 5 12:38:53 2011 No.3337390 >>3337384 is butthurt because he didn't think of it

>>	Anonymous Tue Jul 5 12:39:53 2011 No.3337395 (8888-888)/8

EK !EKFQOBUFnQ Tue Jul 5 12:43:37 2011 No.3337408 [DELETED]

File: 11 KB, 533x603, chess_transformer.png [View same] [iqdb] [saucenao] [google]

>>3337395
another correct solution! well done :)

kk, a new puzzle, chess related again.
start on the green square, you are a chess piece with the power to transform into other chess pieces (but not a king or queen)
you must try to get to the red square, but you can only mutate a maximum of 2 times

GOD MODE: do it in as few moves as possible.

you must not land on any grey squares, these are walls. knights can jump over them, but can not land on them, all other pieces cannot traverse them.

>>	EK !EKFQOBUFnQ Tue Jul 5 12:46:37 2011 No.3337418 >>3337408 multiple solutions are possible, HINT: at least one of your transformations must be a knight to suceed.

>>	>>3337332 Tue Jul 5 12:51:53 2011 No.3337437 >>3337354 I also got the other correct. It's 20.

>>	EK !EKFQOBUFnQ Tue Jul 5 12:52:37 2011 No.3337448 >>3337437 what is 20? the circle one? its possible to make 22 sections, a pic ITT proved it is possible.

>>	Anonymous Tue Jul 5 12:52:53 2011 No.3337444 >>3337390 no samefag, this problem is fucking trivial if you can do that. 8888 - 888 / 8. derp. also: 8(88inverseprimecountingfunction(88/8*8) - binarylog(8)) fucking elegant

>>	Anonymous Tue Jul 5 12:53:53 2011 No.3337455 >>3337373 EK is a fucking idiot. Still doesn't understand that the answer is 20.

>>	Anonymous Tue Jul 5 12:54:53 2011 No.3337459 File: 18 KB, 602x862, Solved.png [View same] [iqdb] [saucenao] [google] >>3337408 10 moves, anyone got less?

>>	EK !EKFQOBUFnQ Tue Jul 5 12:56:37 2011 No.3337465 >>3337459 nice, that looks like a very efficient solution. erm, HARD MODE: you may only use each mutation once, (so try it again, only being a bishop 1 time)

>>	EK !EKFQOBUFnQ Tue Jul 5 12:57:37 2011 No.3337471 >>3337455 troll or stupid? the circle puzzle asks for the maximum, a picture here proves that 22 is possible, and i independently got 22 as a solution myself. see: >>3337206

>>	Anonymous Tue Jul 5 12:58:53 2011 No.3337476 File: 19 KB, 602x862, Solved2.png [View same] [iqdb] [saucenao] [google] >>3337465 Okay, 11 moves.

>>	Anonymous Tue Jul 5 12:59:53 2011 No.3337487 >>3337471 absolute bullshit you got it yourself. you can't do math for shit EK. prove me wrong and answer the question in >>3337242

>>	Anonymous Tue Jul 5 13:01:53 2011 No.3337497 >>3337459 8

>>	Anonymous Tue Jul 5 13:02:53 2011 No.3337500 File: 37 KB, 533x603, 1309884217885.png [View same] [iqdb] [saucenao] [google] >>3337408

EK !EKFQOBUFnQ Tue Jul 5 13:04:37 2011 No.3337508 [DELETED]

>>3337476
nice! probably the most efficient solution with the new rules in palce. well done. :)

>>3337487
i just drew it, and then counted them using the fill tool in paint. i dont know the mathematical formula for it, but each new line i drew i made cross all of the other lines i had also drawn.

>>3337497
really? how? image please?

>>3337500
2 mutations only please, you used 3.

>>	Anonymous Tue Jul 5 13:04:53 2011 No.3337505 File: 21 KB, 548x531, chess.png [View same] [iqdb] [saucenao] [google] 13, but only one mutation.

>>	Anonymous Tue Jul 5 13:04:53 2011 No.3337506 >>3337500 >you can only mutate a maximum of 2 times

>>	Anonymous Tue Jul 5 13:05:53 2011 No.3337511 >>3337505 9 to 10 is impossible, but one mutation is still viable with only one more move

>>	EK !EKFQOBUFnQ Tue Jul 5 13:06:09 2011 No.3337516 >>3337515 14 moves, and yep, that works. well done. :)

>>	Anonymous Tue Jul 5 13:06:53 2011 No.3337515 File: 21 KB, 548x531, fixd.png [View same] [iqdb] [saucenao] [google] >>3337505 fix'd

>>	Anonymous Tue Jul 5 13:07:53 2011 No.3337517 File: 20 KB, 533x603, 1309884217885.png [View same] [iqdb] [saucenao] [google] >>3337408

>>	Anonymous Tue Jul 5 13:07:53 2011 No.3337519 >>3337497 I'm going to call bullshit on this, unless you can show me. It takes that many moves to get through the knight portion of the puzzle itself

>>	EK !EKFQOBUFnQ Tue Jul 5 13:09:37 2011 No.3337523 >>3337519 >459's solution looked very efficient, i doubt you can cut another 2 moves off it.

>>	Anonymous Tue Jul 5 13:12:53 2011 No.3337533 File: 18 KB, 533x603, 1309884217885 (1).png [View same] [iqdb] [saucenao] [google] 1

>>	Anonymous Tue Jul 5 13:12:53 2011 No.3337537 File: 14 KB, 533x603, 1309884217885 (1).png [View same] [iqdb] [saucenao] [google] >>3337508 I can mutate as much as I please but here I am with 2.

>>	EK !EKFQOBUFnQ Tue Jul 5 13:14:37 2011 No.3337544 >>3337537 identical to >476's solution.

>>	Anonymous Tue Jul 5 13:14:53 2011 No.3337541 >>3337537 This looks familiar....

>>	Anonymous Tue Jul 5 13:18:53 2011 No.3337556 File: 12 KB, 533x603, 1309884217885.png [View same] [iqdb] [saucenao] [google] >>3337544 Last time I'm doing this shit.

EK !EKFQOBUFnQ Tue Jul 5 13:20:18 2011 No.3337568
File: 377 KB, 493x348, za1.png [View same] [iqdb] [saucenao] [google]

>>3337556
every fucking time we have a graphical puzzle niggers always pull this shit and try going out of the boundaries. INB4 someone being a rook and just using portals to get from green to red...

>>	Anonymous Tue Jul 5 13:20:53 2011 No.3337566 >>3337533 You touched a grey square faggot cheater.

>>	Anonymous Tue Jul 5 13:22:53 2011 No.3337574 >>3337568 Well that saved me about a minute in paint.

>>	Anonymous Tue Jul 5 13:23:53 2011 No.3337578 >>3337568 I'm a bishop. I moved diagonally through the 4th dimension of space.

>>	Anonymous Tue Jul 5 13:23:53 2011 No.3337581 >>3337408 This would be more interesting if there was another solution. You can't use the lower route with only two mutations. And what's with those three white squares that are impossible to get to?

>>	Anonymous Tue Jul 5 13:23:53 2011 No.3337583 >>3337408 >be pawn >print puzzle >fold paper >0 moves

>>	Anonymous Tue Jul 5 13:24:53 2011 No.3337589 >>3337581 That's what the 4th dimension of space is for.

EK !EKFQOBUFnQ Tue Jul 5 13:25:37 2011 No.3337593 [DELETED]

>>3337581
lol, i dunno, when i made the puzzle i planned 2 or 3 different routes, and then decided to spam a few more white squares to hide the roites and make them less obvious, but in places that would probably be red herrings and not be of value to any solutions.
the 3 white squares down there are kinda too obviously red herrings, maybe i should have moved them closer to the main routes...

>>	Anonymous Tue Jul 5 13:27:53 2011 No.3337603 File: 211 KB, 529x352, dr392d17.jpg [View same] [iqdb] [saucenao] [google] >>3337593 >Allergic to red herrings

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